[PATCH RFC 68/77] sfc: Update MSI/MSI-X interrupts enablement code

Alexander Gordeev
2013-10-02T10:49:24Z

As result of recent re-design of the MSI/MSI-X interrupts enabling
pattern this driver has to be updated to use the new technique to
obtain a optimal number of MSI/MSI-X interrupts required.

Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
---
drivers/net/ethernet/sfc/efx.c | 18 +++++++++++-------
1 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c
index 07c9bc4..184ef9f 100644
--- a/drivers/net/ethernet/sfc/efx.c
+++ b/drivers/net/ethernet/sfc/efx.c
@@ -1261,21 +1261,24 @@ static int efx_probe_interrupts(struct efx_nic *efx)
n_channels += extra_channels;
n_channels = min(n_channels, efx->max_channels);

- for (i = 0; i < n_channels; i++)
- xentries[i].entry = i;
- rc = pci_enable_msix(efx->pci_dev, xentries, n_channels);
- if (rc > 0) {
+ rc = pci_msix_table_size(efx->pci_dev);
+ if (rc < 0)
+ goto msi;
+
+ if (rc < n_channels) {
netif_err(efx, drv, efx->net_dev,
"WARNING: Insufficient MSI-X vectors"
" available (%d < %u).\n", rc, n_channels);
netif_err(efx, drv, efx->net_dev,
"WARNING: Performance may be reduced.\n");
- EFX_BUG_ON_PARANOID(rc >= n_channels);
n_channels = rc;
- rc = pci_enable_msix(efx->pci_dev, xentries,
- n_channels);
}

+ EFX_BUG_ON_PARANOID(n_channels > ARRAY_SIZE(xentries));
+ for (i = 0; i < n_channels; i++)
+ xentries[i].entry = i;
+
+ rc = pci_enable_msix(efx->pci_dev, xentries, n_channels);
if (rc == 0) {
efx->n_channels = n_channels;
if (n_channels > extra_channels)
@@ -1293,6 +1296,7 @@ static int efx_probe_interrupts(struct efx_nic *efx)
efx_get_channel(efx, i)->irq =
xentries[i].vector;
} else {
+msi:
/* Fall back to single channel MSI */
efx->interrupt_mode = EFX_INT_MODE_MSI;
netif_err(efx, drv, efx->net_dev,
--
1.7.7.6